Evaluating Risk of Incident Diabetes Between Patients Who Used Lovastatin and Red Yeast Rice Prescriptions

Objective: This study aimed to evaluate the risk of incident diabetes between people who used lovastatin and red yeast rice (RYR) prescriptions. Methods: A retrospective cohort study was performed to analyze the real-world database of Taiwan's National Health Insurance. We identified the RYR cohort, which included 34,504 persons age 20 years or older who began their use of a RYR prescription in 2010-2014. A comparison cohort of 34,504 adults beginning the use of lovastatin was selected from the same dataset, which was matched by age and sex. Both cohorts had no diabetes before the use of the medications. Events of incident diabetes in 2000-2015 were ascertained from medical claims. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of incident diabetes associated with the use of RYR prescriptions were calculated. Results: The incidences of diabetes for the RYR cohort and the lovastatin cohort were 1.01 and 2.59 per 100 person-years, respectively (P < 0.0001). Compared with the lovastatin cohort, the adjusted HR of incident diabetes was 0.46 (95% CI 0.43-0.50) for people who used RYR prescriptions. The association between reduced incident diabetes and use of RYR prescriptions was significant in various subgroups. There was a dose-response relationship between RYR prescriptions and the reduced risk of incident diabetes. Conclusion: We raised the possibility that people who used RYR prescriptions may have a lower risk of incident diabetes compared with the lovastatin cohort. Keywords: diabetes, lovastatin, red yeast rice, risk